Fix autocompleting stream names inside message editing.
Fix autocompleting stream names inside message editing.

Fixes #2577.

synicalsyntax/zulip,jackrzhang/zulip,kou/zulip,showell/zulip,zacps/zulip,Galexrt/zulip,shubhamdhama/zulip,synicalsyntax/zulip,rht/zulip,zacps/zulip,shubhamdhama/zulip,brainwane/zulip,joyhchen/zulip,vaidap/zulip,arpith/zulip,jrowan/zulip,rht/zulip,aakash-cr7/zulip,joyhchen/zulip,kou/zulip,niftynei/zulip,susansls/zulip,amyliu345/zulip,mahim97/zulip,dattatreya303/zulip,rishig/zulip,tommyip/zulip,niftynei/zulip,susansls/zulip,synicalsyntax/zulip,punchagan/zulip,tommyip/zulip,PhilSk/zulip,punchagan/zulip,dhcrzf/zulip,eeshangarg/zulip,kou/zulip,KingxBanana/zulip,zacps/zulip,sonali0901/zulip,showell/zulip,amanharitsh123/zulip,dattatreya303/zulip,brockwhittaker/zulip,verma-varsha/zulip,shubhamdhama/zulip,vaidap/zulip,christi3k/zulip,vabs22/zulip,punchagan/zulip,kou/zulip,dawran6/zulip,j831/zulip,jphilipsen05/zulip,showell/zulip,andersk/zulip,andersk/zulip,eeshangarg/zulip,isht3/zulip,blaze225/zulip,andersk/zulip,KingxBanana/zulip,mahim97/zulip,ryanbackman/zulip,Juanvulcano/zulip,jackrzhang/zulip,dhcrzf/zulip,zulip/zulip,christi3k/zulip,eeshangarg/zulip,PhilSk/zulip,vaidap/zulip,timabbott/zulip,AZtheAsian/zulip,joyhchen/zulip,Diptanshu8/zulip,sharmaeklavya2/zulip,blaze225/zulip,brainwane/zulip,Galexrt/zulip,hackerkid/zulip,Juanvulcano/zulip,vaidap/zulip,andersk/zulip,zacps/zulip,synicalsyntax/zulip,andersk/zulip,brainwane/zulip,cosmicAsymmetry/zulip,punchagan/zulip,brockwhittaker/zulip,jphilipsen05/zulip,amyliu345/zulip,arpith/zulip,dawran6/zulip,vabs22/zulip,souravbadami/zulip,j831/zulip,punchagan/zulip,susansls/zulip,verma-varsha/zulip,isht3/zulip,vabs22/zulip,timabbott/zulip,hackerkid/zulip,SmartPeople/zulip,hackerkid/zulip,Galexrt/zulip,synicalsyntax/zulip,zacps/zulip,hackerkid/zulip,JPJPJPOPOP/zulip,samatdav/zulip,sharmaeklavya2/zulip,dattatreya303/zulip,dhcrzf/zulip,jainayush975/zulip,dawran6/zulip,dawran6/zulip,jainayush975/zulip,amyliu345/zulip,amanharitsh123/zulip,ryanbackman/zulip,zulip/zulip,isht3/zulip,samatdav/zulip,AZtheAsian/zulip,KingxBanana/zulip,tommyip/zulip,sonali0901/zulip,timabbott/zulip,rishig/zulip,tommyip/zulip,andersk/zulip,shubhamdhama/zulip,vaidap/zulip,souravbadami/zulip,AZtheAsian/zulip,sharmaeklavya2/zulip,joyhchen/zulip,showell/zulip,aakash-cr7/zulip,joyhchen/zulip,rht/zulip,hackerkid/zulip,KingxBanana/zulip,arpith/zulip,jackrzhang/zulip,verma-varsha/zulip,kou/zulip,Diptanshu8/zulip,rishig/zulip,verma-varsha/zulip,Juanvulcano/zulip,vabs22/zulip,christi3k/zulip,timabbott/zulip,shubhamdhama/zulip,hackerkid/zulip,vaidap/zulip,amanharitsh123/zulip,sharmaeklavya2/zulip,jrowan/zulip,rishig/zulip,jainayush975/zulip,ryanbackman/zulip,sharmaeklavya2/zulip,zulip/zulip,christi3k/zulip,kou/zulip,blaze225/zulip,dawran6/zulip,Diptanshu8/zulip,amanharitsh123/zulip,jackrzhang/zulip,Juanvulcano/zulip,dattatreya303/zulip,zulip/zulip,isht3/zulip,brainwane/zulip,ryanbackman/zulip,AZtheAsian/zulip,verma-varsha/zulip,rht/zulip,souravbadami/zulip,isht3/zulip,jrowan/zulip,timabbott/zulip,zacps/zulip,niftynei/zulip,Juanvulcano/zulip,jrowan/zulip,amyliu345/zulip,JPJPJPOPOP/zulip,aakash-cr7/zulip,brainwane/zulip,AZtheAsian/zulip,christi3k/zulip,vabs22/zulip,verma-varsha/zulip,amanharitsh123/zulip,jackrzhang/zulip,dattatreya303/zulip,brockwhittaker/zulip,j831/zulip,joyhchen/zulip,mahim97/zulip,Diptanshu8/zulip,jackrzhang/zulip,Juanvulcano/zulip,vabs22/zulip,rht/zulip,brockwhittaker/zulip,eeshangarg/zulip,SmartPeople/zulip,showell/zulip,eeshangarg/zulip,Diptanshu8/zulip,andersk/zulip,niftynei/zulip,dattatreya303/zulip,dhcrzf/zulip,brockwhittaker/zulip,jainayush975/zulip,arpith/zulip,arpith/zulip,eeshangarg/zulip,aakash-cr7/zulip,dawran6/zulip,jrowan/zulip,susansls/zulip,SmartPeople/zulip,rishig/zulip,rishig/zulip,zulip/zulip,PhilSk/zulip,jphilipsen05/zulip,sonali0901/zulip,JPJPJPOPOP/zulip,jphilipsen05/zulip,tommyip/zulip,cosmicAsymmetry/zulip,jphilipsen05/zulip,cosmicAsymmetry/zulip,synicalsyntax/zulip,jphilipsen05/zulip,dhcrzf/zulip,Galexrt/zulip,mahim97/zulip,JPJPJPOPOP/zulip,KingxBanana/zulip,amanharitsh123/zulip,samatdav/zulip,susansls/zulip,PhilSk/zulip,j831/zulip,kou/zulip,ryanbackman/zulip,cosmicAsymmetry/zulip,Galexrt/zulip,punchagan/zulip,timabbott/zulip,showell/zulip,brockwhittaker/zulip,susansls/zulip,eeshangarg/zulip,SmartPeople/zulip,rht/zulip,sonali0901/zulip,shubhamdhama/zulip,amyliu345/zulip,cosmicAsymmetry/zulip,sonali0901/zulip,tommyip/zulip,punchagan/zulip,souravbadami/zulip,sonali0901/zulip,christi3k/zulip,amyliu345/zulip,sharmaeklavya2/zulip,samatdav/zulip,jackrzhang/zulip,zulip/zulip,blaze225/zulip,zulip/zulip,showell/zulip,Galexrt/zulip,synicalsyntax/zulip,jrowan/zulip,arpith/zulip,isht3/zulip,samatdav/zulip,PhilSk/zulip,tommyip/zulip,SmartPeople/zulip,j831/zulip,PhilSk/zulip,cosmicAsymmetry/zulip,brainwane/zulip,rishig/zulip,AZtheAsian/zulip,SmartPeople/zulip,aakash-cr7/zulip,souravbadami/zulip,KingxBanana/zulip,souravbadami/zulip,Diptanshu8/zulip,mahim97/zulip,niftynei/zulip,shubhamdhama/zulip,niftynei/zulip,mahim97/zulip,blaze225/zulip,jainayush975/zulip,dhcrzf/zulip,JPJPJPOPOP/zulip,JPJPJPOPOP/zulip,samatdav/zulip,Galexrt/zulip,rht/zulip,jainayush975/zulip,blaze225/zulip,ryanbackman/zulip,timabbott/zulip,hackerkid/zulip,j831/zulip,aakash-cr7/zulip,dhcrzf/zulip,brainwane/zulip